Radiation curable resin composition

Abstract

The present invention provides a curable composition, comprising: a (meth)acrylate urethane compound derived from a polypropylene glycol or a propyleneoxide ethyleneoxide copolymer glycol having a molecular weight between 1,000 and 13,000 and an amount of unsaturation less than 0.01 meq/g. The liquid curable resin composition of the present invention has improved liquid stability and can produce cured products having superior mechanical characteristics by polymerization. The composition further comprises preferably a primary or secondary amine. The liquid curable resin composition can be used as a coating material for optical fibers, adhesives, and the like. The composition is particularly suitable as a coating material for optical fibers for which long-term stability is required.

1. A liquid radiation curable resin composition for optic coating materials comprising:
 a (meth)acrylate urethane compound derived from a polypropylene glycol or a copolymer comprising propyleneoxide and ethyleneoxide (hereinafter: said polypropylene glycol) having a molecular weight of between 1,000 and 13,000 and an amount of unsaturation of less than 0.01 meq/g.  
 
     
     
       2. The composition of  claim 1 , wherein said polypropylene glycol has a molecular weight between 2,000 and 8,000. 
     
     
       3. The composition according to  claim 1 , wherein said polypropylene glycol has an amount of unsaturation between 0.0001 and 0.009 meq/g. 
     
     
       4. The composition of  claim 1 , wherein the (meth)acrylate urethane compound further comprises, within the backbone, other polymeric units. 
     
     
       5. The composition according to  claim 4 , wherein the other polymeric units include polyethers, polyesters, polycarbonates, polyolefins, copolymers thereof and mixture therefrom. 
     
     
       6. The composition according to  claim 1 , wherein the (meth)acrylate urethane compound is derived from aromatic and/or aliphatic diisocyanates. 
     
     
       7. The curable composition according to  claim 1 , wherein the urethane compound is prepared by reacting
 (a. 1.) said polypropylene glycol, and optionally  
 (a. 2.) a further polyol or mixture of polyols  
 (b) a polyisocyanate, and  
 (c) a (meth)acrylate containing a hydroxyl group.  
 
     
     
       8. A curable resin composition for optical fibers comprising (a) 40-95 wt % of polyurethane having a polyoxyalkylene structure, in which the weight ratio of propylene oxide and ethylene oxide is 100:0 to 80:20, and an ethylenically unsaturated group, (b) 3-50% of mono-functional (meth)acrylate of which the homopolymer has a glass transition temperature of 20 C. or less, and (c) 0.01-5 wt % of primary or secondary amine compound, wherein wt % is based on the total amount of the components (a), (b), and (c). 
     
     
       9. A cured product obtained by curing the curable resin composition according to  claim 8 , wherein the amount of hydrogen gas generated when the cured product is allowed to stand at 100 C. for two days is 2.0 μl/g or less. 
     
     
       10. A substrate comprising a cured coating obtained by radiation curing the composition according to  claim 1 . 
     
     
       11. The substrate according to  claim 10 , wherein the substrate is a bare optical glass fiber, an optical glass fiber coated with a primary coating, an optical glass fiber coated with a secondary coating, at least two coated optical glass fibers or at least 2 ribbons comprising at least two coated optical glass fibers. 
     
     
       12. An optical fiber, ribbon or cable comprising at least one coating obtained by curing the curable composition according to  claim 1 . 
     
     
       13. The composition of  claim 1 , having a modulus in the range of 0.1-10 MPa after cure. 
     
     
       14. The composition of  claim 1  further comprising a polymerizable vinyl monomer. 
     
     
       15. The composition of  claim 14  wherein said polymerizable vinyl monomer includes at least one component selected from the group consisting of nonylphenol EO-modified acrylate, lauryl acrylate, and nonylphenol PO-modified acrylate. 
     
     
       16. The composition of  claim 14  wherein said polymerizable vinyl monomer includes at least one component selected from the group consisting of N-vinylpyrrolidone, N-vinylcaprolactam, vinyl imidazole, and vinylpyridine. 
     
     
       17. The composition of  claim 14  wherein said polymerizable vinyl monomer includes a poly(meth)acrylate monomer. 
     
     
       18. The composition of  claim 14  wherein said polymerizable vinyl monomer includes tripropylene glycol diacrylate. 
     
     
       19. The composition of  claim 14  wherein said polymerizable vinyl monomer includes propoxylated neopentyl glycol diacrylate. 
     
     
       20. The composition of  claim 14  wherein said polymerizable vinyl monomer includes isodecyl acrylate. 
     
     
       21. The composition of  claim 14  wherein said polymerizable vinyl monomer includes ethoxylated nonylphenol acrylate. 
     
     
       22. The composition of  claim 14  wherein said polymerizable vinyl monomer includes 1,6-hexane diol diacrylate. 
     
     
       23. The composition of  claim 1  further comprising mercaptopropyl trimethoxysilane. 
     
     
       24. The composition of  claim 1  having a cure speed of 0.5 J/cm 2  or less. 
     
     
       25. The composition of  claim 1  comprising 20-80 wt. %, relative to the total weight of the composition, of said urethane compound. 
     
     
       26. The composition of  claim 1  having, after cure, a glass transition temperature in the range of −70° C. to −30° C.